<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="https://cdn.jsdelivr.net/npm/vue@2.7.14/dist/vue.js"></script>
</head>
<body>
  <div id="app">
    <p>请选择你要购买的书籍</p>
    <ul v-for="i in arr">
        <li>
          <span>{{i.name}}</span>
          <button @click="i.count++">买书</button>
        </li>
      </ul>
    <table border="1" width="500" cellspacing="0">
      <tr>
        <th>序号</th>
        <th>书名</th>
        <th>单价</th>
        <th>数量</th>
        <th>合计</th>
      </tr>
      <tr v-for="(i,e) in arr">
        <th>{{e+1}}</th>
        <th>{{i.name}}</th>
        <th>{{i.price}}</th>
        <th>{{i.count}}</th>
        <th>{{i.price * i.count}}</th>
      </tr>
    </table>
    <p>总价格为:{{xx}} </p>
  </div>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        arr: [
          {
            name: "水浒传",
            price: 107,
            count: 0,
          },
          {
            name: "西游记",
            price: 192,
            count: 0,
          },
          {
            name: "三国演义",
            price: 219,
            count: 0,
          },
          {
            name: "红楼梦",
            price: 178,
            count: 0,
          },
        ]
      },
      computed:{
      xx(){
        return this.arr.reduce((i,e)=> i+ (e.price * e.count) ,0)
      }
     }
    })
  </script>
</body>
</html>